Drill-stem for rotary drilling-machines.



E. B. GRBVE.

DRILL STEM FOR ROTARY DRILLING MACHINES. APPLICATION FILED FEB. 20,1914.

1,117,835, Patented Nov. 17, 1914.

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UNITED STATES PATENT OFFICE.

EDGAR E. GREVE, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO OIL WELL SUPPLYCOMPANY, OF PITTSBURGH, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

DRILL-STEM FOR ROTARY DRILLING-MACHINES.

Original application filed April 9, 1913, Serial No. 759,958.

Specification of Letters Patent.

1914, Serial No. 820,018.

To all whom it may concern:

Be it known that I, EDGAR E. GREVE, a citizen of the United States,residing at Pittsburgh, in the county of Allegheny and State ofPennsylvania, have invented certain new and useful Improvements inDrill- Stems for Rotary Drilling-Machines; and

. where employed in connection with a rotary table, or turn-table, anddevices for imparting the rotary motion of the table directly to thedrill stem and drilling string as in drilling Artesian or oil wells.

The object of my invention is to insure an uninterrupted and unimpededfeed of the drill stem and string as well as to facilitate the jumpingof the drill when required.

Heretofore the drill stems commonly employed have been of two generalcharacters, viz., in the form of pipe having a circular cross section,in which case the means for transmitting the movement of the table tothe drill stem has-been of a character to grip, bite into, or indent thestem, thus impeding the drilling feed of the stem as Well as causing adeterioration of the stem, or else the drill stem has been ofnon-circular or polygonal cross section to provide means on the drillstem whereby the drill stem might be loosely held and the rotation ofthe table imparted thereto. In the latter case, the means fortransmitting the motion of the rotary table to the drill stem and stringhas, where it engaged the drill stem, required to be of a configurationcorresponding with the periphery of the drill stem, consequently anyirregularities on the surface of the drill stem, other than thoseprovided for, tend to interfere with and impede the feed and jumping ofthe drill.

Drill stems as commonly employed with rotary drilling machines arerequired to be of from thirty to thirty-six feet in length, more orless, and for convenience. in manufacture as well as in use arecomprised of sections having screw thread connections. As a consequence,if the cross section of the stem is non-circular or polygonal itfrequently happens that the abutting sections when screwed together donot coincide and produce the uniform exterior surface of the stemnecessary to permit an uninterrupted feed of the drill string and anunimpeded jumping of the drill. To overcome these objections insectional drill stems for rotary drilling machines, I interpose betweenthe sections of a drill stein a filler, preferably a compressible gasketof any suitable material whereby the coincidence of the abuttingsections may be secured without straining the threaded connections ofthe sections and without lost motion between the sections, and such aconstruction embodies the main feature of my invention.

There are other, minor, features of invention involving particularcombinations and elemental features of construction, all of which willhereinafter more fully appear.

As a matter of illustration, and without intent of limitation thereby, Ihave chosen to show that form of my invention wherein are employed adrill stem of general cylindrical form with diametrically.disposed ribson its exterior and a rotary drilling machine having a rotary table withdrive pins, a drive-ring and a bushing having a central aperture ofnon-circular cross section for the drill stem, said central aperture ofthe inner bushing corresponding with the cross section of the drillstem, butit is to be understood that the drill stem may be of any othercross section which provides means for enabling the rotary movement ofthe table to be imparted to the drill stem, and the central opening ofthe bushing will correspond to the cross-section chosen for thedrill-stem.

In the drawings chosen for the purpose of illustrating my invention, thescope whereof is pointed out in the claims, Figure 1 is a verticalsectional view of a hydraulic rotary drilling machine, and a view inelevation of a drill stem embodying my invention, parts of the drillstem broken away, showing the relations of the drill stem and the rotarytable by which it is actuated. Fig. 2 is a horizontal sectional view ofa portion of the rotary table, the drive-ring, the bushing, and thedrill stem, taken in the plane of the line 2-2, Fig. 1. Fig. 3 isalongitudinal central section of a portion of a drill stem of thecharacter shown in Figs. 1 and 2, show- Fig. 4 is a View in elevation ofthe portions of the two drill sections shown in Fig. 3; and Fig. 5 is ahorizontal sectional view of a modified form of drill stem and thecentral bushing of the rotary table required to opcrate the same.

Like symbols refer to like parts whereever they occur.

I will now proceed to describe my invention more fully so that othersskilled in the art to which it appertains may apply the same.

In the drawings, 1 indicates suitable skids or sills for the support ofthe bedplate 2 of a rotary table 9 with which a sectional drill stem isemployed. The bedplate 2 has an annular race-way 2* for the rolls 3which support the rotary table, and on said bed-plate 2, radiallydisposed with relation to the annular race-way 2, is a pillow block orhearing 4 for the inner end of a driving shaft 5, the outer end of saiddriving shaft having a bearing in a second pillow block 4 On the shaftintermediate of the pillow blocks or bearings 4, 4 is a loose sprocketwheel 6 and a clutch 7 for connecting the loose sprocket wheel to theshaft. The inner end of drive shaft 5 is provided with a pinion 8secured to said shaft, which pinion engages an annular rack on the undersurface of the rotary table.

9 indicates a rotary table provided with a central opening for thereception of bushings and for the passage of a drill stem, andsurrounding said central opening on the dependent portions of the tableis an annular race-way 9 corresponding to the race-way 2 for thereception of rolls 3 on which said rotary table 9 rests and travels. Atthe upper part and under surface of the rotary table 9' is an annularrack 10 with which the pinion 8 on driving shaft 5 meshes to cause therotation of the table 9, and in the periphery of the table intermediateof said rack 10 and race-way 9 is an annular groove 9' for the receptionof a thrust ring 11. The thrust ring 11 may be made in sections boltedor otherwise connected when in place in groove 9 and is provided withpendent straps or foot extensions 11' by which it is bolted to thebed-plate 2 to support the rotary table 9 under the thrust of the driveshaft 5.

'12 indicates pin holes in the upper surface ofthe rotary table 9 forthe reception of drive-pins 13 which drive pins are secured to the tableby cross-pins 13 passed through radially disposed pin holes in the planeof the thrust groove 9". The drive-pins 13 serve to cause the drive-ringor outer bushing 14 to revolve with the table, and may also, whendesired, be utilized as fulcrums on which to pivot levers for actuatingslips.

to the drill stem through the intermediary or inner bushing 15, whichlatter engages the drill stem. These bushings are loosely connected Witheach other and with the table so as to be readily removable from thetable and from each other. In the preferred form these bushings areannular, the outer bushing or drive ring 14 having openings 14 for thepassage of drive-pins 13, and vertical grooves 14 forthe reception ofribs or feathers 15 on the periphery of the inner bushing 15, and theinner bushing 15 having on its interior grooves 15 for the reception ofribs or feathers on the drill stem. The outer bushing 14 is supported onthe rotary table by the flange 14 through which the drive-pins 13 pass,and the inner bushing 15 is'supported in the outer bushing 14 by reasonof the flange 15, the tapering form of the central opening of bushing 14and the exterior tapering form of bushing 15, as indicated in Fig. 10fthe drawings. While the drill stem is preferably of the cross sectionshown in the principal figures of the drawing, and the-bushings annular,as shown in said figures, this is not essential, as the drill stem andbushing may be of any form which will cause the drill stem to rotatewith the bushings and the bushings to rotate with the table, as forinstance, polygonal in cross section as shown at 14 15 and 16 in Fig. 5of the drawings,

provided always that the drill-stem opening is in the axis of rotationof the table.

16 indicates one form of a sectional drill stem embodying my inventionand adapted for use in connection with a rotary table having a bushingsuch as shown in Figs. 1 and 2 of the drawings. Of course, the crosssection of the drill stem must be of a character to be engaged by theinner bush ing if it is to be rotated thereby, therefore the drill stem16, in the present instance, is shown as cylindrical, having atdiametrically opposite points on its periphery longi tudinal ribs orfeathers 16 adapted to slide in the vertical grooves 15 of the innerbushing 15. The drill stem as'an entirety is usually some thirty feet inlength, more or less, and is made up of sections about ten feet long,said sections having male and female threaded connections as at 16, Fig.3. In order to obtain an uninterrupted feed of the drill-stem and drillduring the rotation thereof by the rotary table, and an unimpededvertical movement of the drill stein in the jumping of the drill it isessential that the abutting sections should be coincident, or thelongitudinal elements of the abutting drill sections should be inalinement.

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In order to permit of the proper alinement of the rib portions 16 or thecoincidence of the abutting sections of a drill stem when the parts arescrewed together, I insert in the joint between the sections a filler17, preferably of a compressible nature, as for instance, a lead gasket.With such a gasket or filler interposed between the sections there willbe no difficulty experienced in alining the ribs 16, or causing theabutting sections of the drill stem to coincide if suflicient force isexerted, and this can be effected without injury to the screw threadconnections of the parts, and without sacrificing the coincidence of thelongitudinal elements, or the rigidity, of the drill stem.

To prevent any tendency of the sections to unscrew, the sections may berecessed at the joints and a plate 18 inserted and secured by screws 19as indicated in Figs. 3 and 4 of the drawing. At the upper end of theupper section of the drill stem the ribs 16 may be, discontinued, as at16, or a suitable plain surface provided just below the collar 16forattaching an elevator to the drill stem.

Having thus described my invention, what I claim and desire to secure byLetters Patent is:

1. A drill stem comprised of sections having a non-circular crosssection and screwthreaded connections, and fillers interposed betweenthe stem sections, whereby a stemv of the sections which comprise thestem.

2. A drill stem comprised of sections having a non-circular crosssection and screw thread connections, and compressible fillersinterposed between the stem sections, whereby a stem having thecorresponding elements of its surface in longitudinal alinement isobtained without straining the threaded connections of the sectionswhich comprise the stem.

3. A drill stem comprised of sections having a non-circular crosssection and screw threaded connections, fillers interposed between thestem sections whereby a stem having the corresponding elements of itssur face in longitudinal alinement is obtained without straining thethreaded connections of the sections, and means whose outer surfaces areflush with the surface of the drill stem for connecting the drill stemsections to prevent creeping and loss of alinement of the correspondingelements of the surface of the drill stem.

In testimony whereof I afiix my signature, in the presence of twosubscribing witnesses.

EDGAR E. GREVE.

Witnesses:

K. H. SESSIONS, SAMUEL E. SWARTZ.

